Bye-Bye Unnecessary Biopsies

May 20, 2008 -- A real-time microscopic technique could lead to earlier diagnosis and treatment of gastrointestinal disorders ranging from reflux disease to colon cancer, new studies suggest.

Called confocal laser endomicroscopy (CLE), the technique may also help to avoid unnecessary biopsies, researchers say.

CLE uses a tiny microscope at the end of an endoscope, a flexible, lighted instrument that is used to view the gastrointestinal tract. Three new studies of the technique were presented at Digestive Disease Week 2008 in San Diego.

"Images are magnified 1,000 times, so we can see microscopic changes throughout the GI tract that we can't see with traditional endoscopy," says Kerry B. Dunbar, MD, a fellow in the division of gastroenterology and hepatology at Johns Hopkins University School of Medicine in Baltimore.

"What that means is that we can detect suspicious activity, such as precancerous cells, immediately," Dunbar tells WebMD.

Without CLE, it can take days or even weeks to get a diagnosis "because we'd have to take photos and then do a biopsy and send it to a pathologist to interpret the results," says Pankaj J. Pasricha, MD, professor of medicine, gastroenterology and hepatology at Stanford University School of Medicine.

"CLE has the potential to revolutionize the field," says Pasricha, who moderated a news conference to discuss the findings.

CLE More Than 90% Accurate

In one study, Dunbar and colleagues performed 2,102 CLE examinations on 1,771 patients. The results were compared with those obtained using traditional endoscopy.

CLE rarely missed any suspicious lesions, Dunbar says. There were a few false positives, "where we thought we saw something on CLE and it turned out to be nothing," she says.

Overall, CLE had an accuracy rate of 91% in the upper GI tract and 93% in the lower GI tract.

In 20% of cases, the CLE results would have changed the diagnosis, Dunbar adds. "Most were cases where we saw signs of dysplasia (abnormal cell growth that is a precursor to cancer) that could not be seen on traditional endoscopy," she says.

The complication rate, chiefly nausea from a fluorescent yellow dye that is injected into patients so doctors can better visualize cells, was less than 1%.

"I do warn patients that they will be yellow for a few hours after the procedure, so they shouldn't plan on having their picture taken," she says.